Engine charcoal and spark plug bonks

413 said

The BIG question not asked yet: How long has the #7 not been firing and wearing out the cylinder wall and rings from not firing. How long has it run to get that much sluge?
Since you bought it? How long? Miles? Did you know it ran on 7 cylinders?

1) Try a shorter plug for #7
2) Clean out the plugged exhaust crossover in intake and heads.
3) Remove sludge with a putty knife, etc.

Now go drive it and see what you've got.

Beyond that, It's a 273. Dump it.

Click to expand...

Guessing since I bought it back in July. Admittedly, don’t recall if I checked all the plugs or if I hit a handful and thought it looked ok enough. Probably only driven the thing 100-150 miles since then.

Everyone keeps telling me “sounds like it runs good! What a find!” Meanwhile, I was trying to figure out why I could never get consistent oil readings and it felt underpowered.

Compression on all cylinders is 143-155 if that tells anyone anything. 150 on #7. Thought this was all pretty promising until I started taking it apart!

Short term solution might be spacers/shorter plug and the clean out Hail Mary while I look into a replacement and start buying some Black Friday engine removal equipment